Air pump



May 26, 1925.

M. B. HOLSTEIN AIR PUMP 7'" 44 Snowdon Filed June 11, 192.4

MW 6 w W Patented May 26, 1925.

UNITED STATES MICHAEL B. HOLSTEIN, OF RICHLAND, PENNSYLVANIA.

AIR PUMP.

Application led June 11, 1924. Serial No. 719,331.

To all 107mm t may] concern Be it known that I, MICHAEL B. HOLSTEIN, a citizen of the United States, residing at Richland, in the vcounty of Lebanon andy State of Pennsylvania, have invented certain new and useful Improvementsin Air Pumps; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to vwhich it appertains to make and use the same.

This invention relates to improvements in air pumps andV more particularly to hand operated high-pressure air pumps of the type disclosed in my Patent 1,330,266, Feb. 10, I1920. The pump illustrated in said patent has proved eflicient in practice, and the primary object of the present invention is to improve pumps of this character, so that they may be manufactured and assembled at less expense than the pump disclosed in said prior patent.

Another object of the invention is to pro vide an air pump having a small number of threaded joints, so that the pump may be manufactured without providing t-he parts with a multiplicity of screwethreads.

QWith the foregoing objects outlined and with other objects in View, which will appear as the description proceeds, the invention consists in the novel features hereinafter described in connection with the accompanying drawings and more particularly pointed out in the appended claims.

Referring to the drawing Fig. 1 is a side view of my improved pump.

Fig. 2 is an enlarged Vertical longitudinal sectional view of the same.

Fig. 3 is a top plan view, partly broken away.

Fig. 4 is a horizontal sectional view on a reduced scale taken on line 4-4 of Fig. 2.

In the drawing, 1 designates a base or standard having laterally directed wings 2 upon which the operator may stand in using the. pump. The base also includes a socket having a nipple 4 connected by a clip 5 to flexible tubing 6, that is adapted to be con nected to the tire or the like to be inflated. rlhe interior of the nipple, communicates with the interior of the socket, as shown at in Fig. 2.

The socket 3 is provided with internal screw threads to engage external screw threads 8 arranged at the lower end of a high pressure cylinder or tubef9,y this threaded joint being one of the'live threaded v joints .in the present construction. y The cylinder 9, to reduce the cost of manufacture, is preferably made of standard tubing and has additional external threads 10 at its' 14 having internal threads engaging 'the threads 10 of the cylinder 9 and holding the v '7 packing ring 18 in compressed relation relatively to the disk 11.V Thecup 14 has an outwardly extending annular flange 15 functioning as a stationary lo-w pressure piston, in a manner hereinafter explained. The joint provided by thethreads 10i, is the second threaded joint in the construction, and the third threaded joint is provided by al gland 16 which surrounds the cylinder 9 and has internal threads engaging the threads 10, for the purpose of forcing a packing ring 17 against the flange 15. This packing ring is in the shape of an' inverted cup washer and it forms an air valve, as will be hereinafter explained. The gland 16 is of annular form and has diametrically opposite flattened sides, as shown at 18 in Fig. 4. These flat portions permit the gland to be tightened or adjusted by an ordinary monkey-wrench. The cylinder 9 has air ports 19 arranged near its upper end and opening into the hollow space in the gland 16. All of these `parts are the stationary portions of the pump, and the movable portions will vnow be described.

Surrounding the cylinder` 9, is a sleeve 20,

which is slidably mounted on the cylinder and is provided at its upper end with an annular cup 21. This cup is provided with a large circular recess 22 and a smaller `circular recess .8, which merge into one-an other. The smaller recess receives an 'annular packing 24 arranged at' the lower end of a packing ring 25, the latter snugly' engaging the exterior surface of the cylinder 9 and being forced against said surface by air pressure, as hereinafter described.

Seated in the larger recess 22 is a conipressible washer 2G which bears at'its inner edge against the ring 24. 1U larger concentric outer low pressure cylinder 2^",

has its lower edge extending` into the re` .l Y cess 22 and bears upon tne washer 2G, to

l provide an air etight'fijoint at thisY point;

Without the useofscreW-tlireads; This low" pressure cylinder may also be formed of' 27, is a circular disk 2S' provided with' at owing to my present construction, this piece of tubing need not be threaded, 'Y

. Resting on the upper edgeof the cylinder least.' three air inlet ports-29 equally dis? tributed over-'the plate.'L Tliisiplat orf diskh QSha's a vcentral aperture' to reeive the 11pper .end of a piston rod 30, thezla'ttr being);

provided 'near its upper end vvith'a` transl.

Vverse.-: rperture to receive the looselylitfting fr pin 3,1, which .is arranged fabove the disk QSgandffu'ncti'ons, topreventfthe .rod fromy mov-ing downwardlyrelatively rto Vthe disk.v

A splitfspring Washer? 32 is. arranged beV tween tliecup -14 'and disk' 28fto prevent vtliese panjts. froin coming together andto absorb; the shocks caused by. the. downward- .movement of the low pressure cylinder 27" relatively to theV stationarycylinder 9.1

The cup 21 has diametrically opposite' inainigzones of the five threaded joints in .the coiistructioinjandthis isf five less" threaded "joints: tiliands Vused inthe construc` tion. disclosed Vin my ilbfove" mentioned pat? ent., The yupperends" of the bolts extend! ltliroughaoro-ss bar or operatinghandle andliave heads 37, Which'bearupon Ioppo- Vs iteienpds of a bow-shapedleajf' springBSj This 4leaf springhas a tendency tyc ,.p ulllupY wardly on the'fheads of the bolts, andther'er by cause tlietlireads3,3"andj34 to interloel withv the 'threads of the cupl 'and prevent the. partsV from" aeci'dentally dis'assenbli'ng;

Froin'Fig, 2, it.` may beseenthat ltheiun-L derside ofV the handle'f26, has' a'rece'ssto"V receive the upper end'ofithelovvpressure1 cylinder 27 Vand ythe disk 28en`d a smaller]` recessisprovi'ded in the' handleto receive the upper end offthe rod" 30""and slightly greater than the lengthof the.: pin 3.1'. to. prevent the, pin from accidentally disconnecting itself Lfrom the rod '80.`

The rod BOhes threads' 40"at its'lowerk end,l to. receive 'a piston 41 offless diameter than the'. inner diameter'of vthe cylinder E);

and a cupgleather Washer 142 is pressedv against the piston by-*a'rinetal Washer43` and a vnut 44'# i The o eration is' as follows :1 The opera-` tor stance, -ujior'iY the Wings' 2 andgra'sp'sthev handle. 3 6, and then moves this handler up and down. As the handlemoves upward-ly, itcarries'with it'tlie low pressure cylinder 27,'. and air.V rushes in to the upper end of this cylinder through one orv more of the apertures, 29; rIhese'apertures are so placed, that even if the disk 28 rotatesabout they ,of y.the Awasher"177 so as to/seul".V the space threaded. apertures to receivey the `tlfaoled. lower eridsfand 3.4'kof tieV rods or bolts, These two threaded joints frinjthe'je the. pin. 3 1.1 Thisre'ces's '391i hasa diameter rod 3), on@ ori more :of "the-:holes '29;' Will be' at one or the "other 'iside ofthe handle its full stroke, and the operator commences to-V force the handle downwardly, some of the air previously'drawn intothe upper end of the 'cylindei'ill be forced downward-V ly past the periphery of the stationary pist0n 0r flange 1 5"endelsv" Pesvthcue" leather 17j into. the-slower?"portionfof Ivthe 10W pressure"cylinder: Thenon the next.

uplstroke ofthe 'pumpgtliiszair Willlbe com# pressedA and" actf "againstitlijef inner surface between the washer "andthe inner-surface" 36;"sothat the air may enter thercylinder an ordinary pieceof"standardtubingiandl'i' Whenther.handIeTrhIEheenpulled up Y ofthe cyl'Inder12T."V Consequently this airm" must travel through; "the Vapertures l19 inyto,` the high'4 pressure cylinder 9, Aand 'asi the 'pis--l ton 41 is moving upwardly. at*tliisrtilne,` this` Vcompressed air will" movel downwardlyY *p ast p thev peripheryof fthe-piston" 411. and. :the: :perl riphery' of the cup 'washr42ginto the-lower:l

end oftlie cylinder. ll'ovvlonfthefrloW-n` stroke of the punip,fzthiscom1ressed air'will be', compressed Ito. aliigher l egreefand Lwill* be passedfout through 'tle f aperture 47' in:v tol the tire or therlike-tolbe'iniited;

the construction,` opertion andA advantages\1 of the invention maybe readily -uriderstood,. but "tol poitjz out' more@ specifically -,thefs'ini plicityY and tle` lpractieebility off the pump,

neoted' erts; Vnitty? f beereadily disassembled it' is deemed advisable to refer Ato fthe" mam` 'y nerV of dismantling*theffconstruction;to d'e-i b1 unscrexvingtheecupillk-and subsequently-- the" gland "-16; frorn the-@stationary cylinder Now if desired, the, rod 30 may lbe raised andl thesrn aller l piston 41J "algrzls its con necte d part-sniaybe retrieved? 1 i lVhlel I 'halvevdiselosel the preferred enibodiment *or* itheJ invention; ,it -is lapparein tf that changes rnayjf be; mede" f. the i details: Withoutjdeprrtiiigfrom thespirit of. the` invention) Ynsf expressed' inthe claims;

"What I cla'ini 'and desire to seeureby LetterslPatentfise 1 1. Air 'ain punipineludingfqa base,` .a l `high pressure sttionalry' cylinder havingiits loweriin end connected to said base, a stationerypis- I ton 'closing-the -upperend-oi seidzfcylinder, a sleeveI slidebly arranged fon the. periphery of said'cylinder,` a tcupl-at'ftheupper end fof said sleeve, a low pressure cylinder having the lower portion ot' its periphery smooth and extending into said cup, a compressible washer arranged in the cup and engaging the lower end ot the low pressure cylinder, an apertured plate arranged at the upper end ot the low pressure cylinder and forming a cap for the latter, a handle arranged above the cap, and tie rods extending through the handle and in threaded connection at their lower ends with said cup.

2. An air pump including a base, a threaded socket, upon said base, a high pressure cylinder having threads at its lower end engaging the threads of the socket, said cylinder having air inlet ports near its upper end and an air outlet port at its lower end, a detachable cap for the upper end of the cylinder forming a stationary piston, a sleeve slidably mounted on the periphery o't the cylinder and provided with a cup, a liexible packing ring associated with the cup and bearing against the outer surface of the cylinder, a low pressure cylinder surrounding the` high pressure cylinder and having the surfaces of its end portions smooth, the lower end of the low pressure cylinder eX- tending into said cup, a plate resting on the upper end of the low pressure cylinder and provided with air inlet ports, a handle ar ranged above said plate, detachable means connecting the handle to the cup, a piston rod having its upper end connected to the handle, a piston arranged in the high pressure cylinder, connected to the rod and being of less diameter than the internal diameter of the high pressure cylinder, and cupwashers connected to said pistons and arranged to permit air to pass by the pistons when the handle is moved in one direction and to prevent air from moving past the pistons when the handle is moved in the opposite direction.

3. In an air pump, a high pressure cylinder, a sleeve slidably mounted on the periphery of said cylinder, an annular enlargement upon the upper portion of said sleeve having a cupped upper surface, packing means connected to the said cupped surface and bearing upon the periphery of the cylinder, a low pressure cylinder having an unthreaded lower end portion loosely iitting in said cupped surface and bearing upon the packing means, and means for forcing the lower' end ot the low pressure cylinder into the cupped portion of the said slidable sleeve.

4. In an air pump, a low pressure cylinder, a cap plate for said cylinder resting loosely upon one end of the latter and provided with at least three apertures equally spaced radially about the axis of the disk, a handle bearing upon said disk and of less width than the diameter of the disk to permit one or more oit said apertures to admit air to the cylinder regardless of the position of the apertures relatively to the aXisot the disk, and means for holding s aid cylinder, disk and handle together.

5. In an air pump, a cylinder having a cap plate, a piston rod extending into the cylinder and having an aperture near one end, a pin extending through said aperture for holding the plate in engagement with the rod, and a handle connected to the cylinder and having a recess in which the pin is housed, said recess being of slightly greater diameter than the length of the pin and having its walls arranged to prevent accidental detachment oi the pin from the rod.

G. In an air pump, a cup provided with packing means, a cylinder having one'of its ends extending into the cup and bearing against the packing means, a plate resting on the opposite end of the cylinder, said cup being provided with screw threaded apertures, a handle bearing upon said plate, a bow-shaped spring bearing upon the handle and normally having its ends extending upwardly, and bolts passing through the ends of the spring and said handle and engaging the threaded apertures of the cup.

7. In an air pump aliigh pressure cylinder, a sleeve slidably mounted upon the eX- terior of said cylinder, an annular enlargement upon the upper end of said sleeve having a cupped ripper' surface, a suitable packing between said sleeve and said cylinder, a low pressure cylinder formed of plain unthreaded tubing loosely fitting within the cupped upper end of the slidable sleeve aforesaid, an annular packing gland forming a seat for the lower end of said low pressure cylinder, a vented closure for the upper end of the last named cylinder, and means for retaining the latter cylinder in air tight contact with its said packing gland.

8. In an air pump a high pressure cylinder, a sleeve slidably mounted upon the eX- terior of said cylinder, an annular enlargement upon the upper end of said sleeve, :t packing-seat cupped out of the upper surface of said enlargement, a second packing seat counterbored concentrically in said first seat, a flanged cup packing ring for the high pressure cylinder resting in said secondseat, an annular packing ring directly surmounting the flange of the said cup packing located in the outermost and uppermost ot said packing seats, a low pressure cylinder formed of plain unthreaded tubing resting at its lower end upon the said outermost annular packing ring` a vented closure for the upper end of the low pressure cylinder. and exterior tie rods arranged and adaptedto operatively connect the sliding sleeve and the vented closurel at opposite ends of the low pressure cylinder.

In testimony whereof I affix my signature.

MICHAEL B. HOLSTEIN. 

